Average

A calculated "central" value of a set of numbers.

It is easy to calculate: Just add up all the numbers, then divide by how many numbers there are.

Example: what is the mean of 2, 7 and 9?

Add the numbers: 2 + 7 + 9 = 18

Divide by how many numbers (i.e. we added 3 numbers): 18 ÷ 3 = 6

So the Mean is 6